Tractor



June 9; 1931. |NN 1,809,344

TRACTOR Original Filed May 13, 1924 2 Shets-Sheet 1 INVENTOR. fioLMA/v H luv/v, BY 2 I v ATTORNEY.

I June 9, 1931. H. H. LINN 1,809,344

TRACTOR Original Filed May 13, 1924 '2 Sheets-Sheet 2' gwuanto'c 6 01/4 70 6, A mvv Patented June 9, 1931 if UNITED STATES HOLMAN HARRY LINN, or-Monars, NEW YORK, ASSIGNOR TO THE LINN 'iyIAmi- FACTURINGY CORPORATION, or MORRIS; NEW-YORK; A. iconro mrion or V YORK Original application filed May 13, 1924,

This case is-a division of application Ser. No. 713,022, filed May 13, 1924:, and relates more particularly to the compensatingdevice which contributes to the flexibility of the track by permitting it to take up freely on uneven surfaces.

The nature of the invention consists in the support and carriage of the idler sprocketsby compensating devices of special construction and arrangement of partsfor the purpose and with the result of maintaining proper track tension for any surface; of automatically taking up wear; and of providing for,

minimum breakage of'sprockets, due to trap ping of obstructions, by permitting, the

sprockets to slip onetoothand thus insure Fig. 2 is a side elevation of one of the track 7 units. m

Fig. 3 is a plan view ofthe slide frame casting. r

Fig. 4 is a side view of the same. I Fig. 5 is a section on line 5- 5 of Fig. 3. Fig. 6 is a front edge view, partly in section. I

According to the invention, the main frame, consisting of longitudinally ranging members 5, is provided with an auxiliary frame consisting of side bars 6 secured in spaced parallel relation to the main frame members by cross bars 7. Hangers 8, secured tothe auxiliary and main frame elements, accommo date atransverse shaft 9, the ends of'which form pivotal or trunnion mountings for load vtransferring elements or'rocker beams 10.

The latter are supported fore and aft by pairs of relatively adjustable runner blocks 11.

The details of therunner blocks are set forth in the parent application.

A roller chain 12 is adapted and arranged to travel over the runner blocks to eliminate friction between them and articulated tracks TRACTOR Serial No. 713,022. Dividedand this application ea August 27, 1928. Serial N0'.'3OV2,36 5. Q v

13. =The latter are suspended on sets of double or twin sprockets 14c and 15 whereofone is a driving sprocket and the other anmidler sprocket. It is with the support-and carriage of the idler sprocket, providing for its'c'omplete responsiveness to changing conditions of stress on the track, that the present case is particularly addressed. Gene-rally speaking" the idler sprockets'are mounted in compensating slide frames, yieldable under spring control to permit the idler sprockets to vary the tension of the articulated orflexible tracks in accordance with varying ground surface con-5 ditions. ,7 a

In order to insure adequate strength and ruggedness to meet the severe service imposed upon them, the slide frames preferably are of unit or integral construction of generallyhair pin forin, consisting of side sills 16 joined at a one end bya yoke 17 and a'bolsterfor the 1st. ter consisting .of a straight transverse member 18. p

The side sills or frame members 16 have continuous grooves or channels 19 and through slots or openings 20. The channelsflfi I i 19 receive the lower fian'gesof the mainvan'd auxiliary frame members 5 and 6, respec-- tively. The through slots or openings insure proper heat treatment. I f Cast integral with the side sills are jourreinforcing webs 22.

, nals 21 for the. shaft or trunnion element 1' of the idler sprocket, the journals having tends loosely through a thrust block or element 25 rigidly secured betweenthe main and auxiliary frame members. Between the 1 thrust 'block and the extremity of the rod 24 there is a heavy coil spring 26, which may be adjusted, as required, through the medium of nuts 27 and'28. Evidently the slide frames and the idler sprockets are held in normal,

position by the springs 26, but are capable of overcoming the resistanceof the springs to provide the necesasry compensating adjust- Y .ment to relieve strain on the tracks.

As set forth in the parent application, the

tracks are self-clearing in the event of buildingup conditions, namely, when rocks,'ice,

wet snow or other substances are trapped between the sprockets and tracks. Such conditions are overcome by the responsive action of the compensating slide which permits the sprockets to slip to forcibly eject the trapped material. Moreover the instant responsivenessofthe slide to permit slippage of the tracks will minimize breakage due to conditions brought about through carelessness or ignorance of a green driver, as, for example, in bad going and in low gear when he steps on it;

;Having described my invention, I claim: A carrier for tractor frames, including a hair-pin frame having side sills and a transverse yoke connecting them at one end, each of said sills being formed with longitudinally ranging channels to permit sliding cooperation ofthe carrier in the tractor frame, and idler-sprocket shaft bearings carried by the sills intermediate their ends and'below said channels.

In testimony whereof I aiiix my signature.

I-IOLMAN HARRY LINN. 

